Alloy of aluminum and beryllium



Patented Aug. 29, 1933 UNITED STATES PATENT OFFICE 1,924,168 ALLOY OF ALUMINUM AND BERYLLIUM No Drawing. Application Serial No.

2Claims.

, This invention relates to alloys in which aluminum predominates, and to which alloys of other metals, beryllium particularly, are added not only to better strength and other mechan- 5 ical characteristics, but also to at once lower the specific gravity of the alloy and to effect greater resistance to atmospheric corrosion and similar influences. 1

It has long been known that the addition of 0 beryllium to aluminum results in an alloy which is considerably lighter than is pure aluminum itself, the lessening of weight varying linearly with the beryllium content. At the same time, the resistance to corrosion is considerably improved as beryllium content increases.

Because of the relatively high cost of beryllium, it is frequently desirable to keep the proportion of this element as low as possible, yet not sacrifice its valuable strengthening effects; 0 For this reason, I have sought for metals which would intensity the effects of beryllium when alloyed with a preponderating amount of aluminum, and this invention relates only to those alloys in which the quantity of aluminum exceeds that of beryllium. I have found that, by the addition of relatively small quantities of molybdenum and/or 1 quantities themselves lnsuflicient to increase the specific gravity oi the alloy so significantly, the effect or beryllium is magnified, and the resulting alloy has materially greater strength, workabilitncastability, bendability, as well as resistance to corrosion, than the simple binary alloy In general, I prefer compositions in which the content 01' aluminum and ninety-eight percent, with running from about to about beryllium Iromabout 25% to about the . aluminum from about December 22, 1931 582,656

40%, with Q the remainder manganese and/or molybdenum from a substantial fraction to about 1% each.

The manganese and/or molybdenum, as well as the beryllium for alloys low in beryllium, may so be added as a master alloy, alloyed with any convenient percentage of aluminum. The manganese and/or molybdenum may also be added directly to an aluminum-beryllium alloy previously made in any of the standardmanners, 05 or the final alloy'can be formed by reduction of convenient manganese and/or molybdenum compounds directly by the previously-formed binary aluminum-beryllium alloy.

The ternary or quaternary alloys made in ac- 70 cordance with this invention are particularlywell suited for castings requiring strength beyond that 01 ordinary aluminum, or even of its stronger alloys, like duralumin. They'are also well adapted for use in sheet form, as.in the 76 case of airplane wings or fuselage parts, or wherever else the combination of ultra-lightness, strength and bendability without breaking is essential.

The percentages are by weight.-

I claim:--

l. A beryllium aluminum alloy con 55% to about 70%, berylto about 40%, and the hallium from about 25% ance, not in excess of approximately 2%, molyb- 35 denum to harden the aluminum eutectic.

2. A beryllium aluminum' alloy containing aluminum from about 55% to about 70%, beryllium from about 25% to about 40%, the two together constituting about 98% of the total, and the balance, not in excess of 2%, being molybdenum to harden the aluminum eutectic.

I JOSEPH KENT SMITH.

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